Everyone knows that Loki is Thor’s arch-nemesis, but what about Loki’s kids? In the original Norse mythology (and the Marvel comics alike), Loki’s children have also made Thor’s life pretty miserable over the years. With Loki now in charge of Asgard, it could be an ideal time to reveal any or all of these villains to be his lieutenants - like Hela (Queen of Hel) and Fenris (a giant wolf) - but in particular we mostly want to see Chris Hemsworth do battle with a Jormungand, a sea serpent so large he literally wraps around the planet.
“Whosoever holds this hammer, if he be worthy, shall possess the power of Thor.” But as we learned in Avengers: Age of Ultron, there’s more than one worthy person wandering around the Marvel Cinematic Universe. One of the most popular is Beta Ray Bill, an alien cyborg who bested Thor in battle and kept the hammer as a prize. Eventually Odin gave Bill his own hammer, Stormbreaker, which sent this strange-looking hero off on his own intergalactic adventures. If Thor: Ragnarok lives up to its name, and turns out to be the last of the title hero’s battles, a post-credits scene where an alien hand picks up Mjolnir could be a real thrill… for anyone in the audience who knows who Bill is.
“Whosoever holds this hammer, if he be worthy, shall possess the power of Thor.” But who says it has to be a “he?” Recently, a female version of Thor has been flying around the Marvel Comics Universe, and was eventually revealed to be Jane Foster herself. Considering just how little Natalie Portman gets to do in the Marvel Cinematic Universe, giving her an opportunity to become the title hero would not only be greatly appealing to the filmmakers, but it would also be a welcome relief in a cinematic universe disproportionately populated with male superheroes.
And hey, remember that time when Thor was a frog?! Oh right, that was stupid. Well, maybe they could just put a frog in the background as a joke or something. That would be kinda funny.
So it turns out that Asgard is real in the Marvel Cinematic Universe. Why not Olympus as well? In the comics, Thor and the demigod Hercules have shared many a beer together, and both have served as members of the Avengers. Revealing that another alien race, not unlike the Asgardians, has an interest on the planet Earth - and that their emissary is an even drunker version of Thor - could be a major reveal in the MCU, and possibly a great set-up for a new franchise.
If Hercules is real, the rest of the Greek pantheon must be real too, which brings us to Ares. The God of War became a major player in the comics as an anti-hero, after many years of being Hercules’ arch-nemesis. So think of Ares as Loki, with his own spin-off and lots and lots of guns. Or like The Punisher, if The Punisher was a god. Either way, he’s a great villain and possibly a great hero to add to the MCU roster.
Thor and Loki are both the sons of Odin, the King of Asgard. But they’re not the only ones. In the original Norse myths, it was the death of Odin’s other son, Balder, that leads directly to the end of the world. And what did the Asgardians call the end of the world? “Ragnarok.” Although Balder hasn’t always been an important character in the comics, it may behoove the makers of Thor: Ragnarok to introduce him to throw a monkey wrench into the long-brewing conflict between Thor and Loki, and possibly either take the throne himself or possibly just die and send the whole galaxy into chaos.
Now that Loki has Odin’s throne, he also has Odin’s kingdom, and Odin’s warriors. Amongst the greatest of those warriors in the comics is Brunnhilde, leader of the Valkyrior, who lead the slain to their proper place in the afterlife. Death in the Marvel Cinematic Universe doesn’t quite work that way, but that doesn’t mean there isn’t a place in the MCU for an all-female Asgardian strike force led by a courageous hero who might one day come to Earth to join various superteams and make a name for herself.
Thor doesn’t have all that many arch-nemeses, honestly. Besides Loki, the biggest name on his enemies list is still probably The Enchantress, an Asgardian who can bend men to her will. One such man is the mighty Skurge, also known as The Executioner, a warrior who would do anything for his lady even though she never reciprocates his desires. Manipulative and powerful, these two could be a major threat to both Thor and Loki, and since The Enchantress’s sister Lorelei has already made an appearance on Marvel’s Agents of S.H.I.E.L.D., she’s probably already in the Marvel Cinematic Universe canon. We just haven’t met her yet.
Now that Thor and Jane Foster are happily in love, it’s time for someone to get in their way. Who better than an ex-boyfriend? In the first Thor, our hero winds up borrowing clothes that used to belong to Jane’s ex, Dr. Donald Blake, who in the comics was Thor’s original human identity. It seemed like a throwaway joke at the time, but why not go the whole nine yards and make him an actual character this time? Besides, the last time Thor and Hulk teamed up on camera (in The Incredible Hulk Returns), Thor and Blake were in separate bodies and drove each other nuts. History might just repeat itself.